Who is starting smoking? An investigation of smoking initiation - - PowerPoint PPT Presentation

Who is starting smoking? An investigation of smoking initiation among all ages using prospectively collected data

Richard Edwards, Kristie Carter, Jo Peace,

Background

• Tobacco industry argues that decision to smoke is an

informed choice by adult smokers

• Previous investigations of prevalence of uptake have

focused on the experience of children and youth

• Mostly use cross-sectional data
• Data from TUS and NZ census suggest uptake occurs

between 15-19 years and between 20-24 years

• Identifying uptake using cross-sectional data may not

be valid, especially among older age groups

Informed Choice

“The risks associated with smoking are universally known, and … smoking is, and should continue to be, a matter of informed adult choice”

Imperial Tobacco NZ Ltd 2010: Submission to the Māori Affairs Select Committee Enquiry into the tobacco industry in Aotearoa and the consequences of tobacco use for Māori

Background

• Tobacco industry argues that decision to smoke is an

informed choice by adult smokers

• Previous investigations of prevalence of uptake have

focused on the experience of children and youth

• Mostly use cross-sectional data
• Data from TUS and NZ census suggest uptake occurs

between 15-19 years and between 20-24 years

• Identifying uptake using cross-sectional data may not

be valid, especially among older age groups

Smoking prevalence by age, 15-24 years, 2006 Census

0% 5% 10% 15% 20% 25% 30% 35%

Male Female

Aims

To assess smoking initiation and quitting rates prospectively across all age ranges using a population- based study

Methods

SoFIE study

• Nationally representative longitudinal survey of the

usually resident population living in private households in NZ.

• Detailed health module asked in waves 3 (2004/5), 5

(2006/7) and 7 (2008/9)

• 15,095 adults responded in all waves (3,5 and 7) (68%

response rate from wave 1)

• Attrition rate highest in youngest, Maori, or “other”

respondents, low income respondents or those with poorer health status.

Smoking Status

• Never smoker, ex-smoker or current smoker status

determined at each wave

• “Current smoker’ if he/she reported to “regularly

smoke one or more tobacco cigarettes per day”

• Classified as initiating smoking if they changed from

a never smoker to a current smoker

• Classified as quitting smoking if they changed from a

current smoker to an ex-smoker

Results - Smoking prevalence by age group, SOFIE Wave 3 data (2004/5)

5 10 15 20 25 15-17 18-19 20-24 25-34 35-44 45-54 55-64 65+ Prevalence

Results - Smoking Initiation

2 4 6 8 10 12 14 16 15-17 18-19 20-24 25-34 35-44 45-54 55-64 65+

Percentage

Age at Wave 3

Smoking Initiation

W 5-7 W 3-5

Initiation rates between waves 3 and 5 and waves 5 and 7 by age group

Results - Quitting

5 10 15 20 25 30 35 15-17 18-19 20-24 25-34 35-44 45-54 55-64 65+

Percentage Age at Wave 3

Quitting Smoking

W 5-7 W 3-5

Percentage of smokers quitting between waves 3 and 5 and waves 5 and 7.

Discussion

• Initiation is rare after age 24 years, but common
• Suggests that industry arguments that decision to

smoke is an “informed choice” may be false

– Mature adults rarely start to smoke – Initaition of smoking by young adults may not represent exercise of informed choice (further research)

• No clear pattern in quitting across age groups
• Efforts to prevent initiation of smoking should

focus on smoking uptake among young adults as well as children